Vat dyes of the thioindigo series and process of making same



' l HERE, E FRANKFORT-ON-THE-MAIN, AND J'E'NS Mfi'LLE-R, 0F HAbTA'U,

GERMANY.

Vdfi' EYES OF THE THIOINDIGO SERIES AND PROCESS OF MAKING AME).

R70 Drawing.

sonicoorm) wherein Ar indicates an arylgroup, which may or, may nototherwise contain substituents such as alkyl halogen, oxyalkyl).

X indicates: NH NH acyl and the group :N:N azocomponentand Y indicates:hydrogen which may be substituted by a metal.

Their probabl constitution is represented by the fol owing generalstructural formula:

co C0 \1 Ar s ,C C s Alr N IX Nnx wherein Ar indicates an arylgroupwhich may or may not otherwise contain substituents (such as allcylhalogen, oxyalkyl), and X indicates hydrogen which may be substituted byan acylgroup, and in which the S-atom oi. the thioindigo ring standsin0- position to NHX.

The o-aminoarylthioglycolic acids for instance may be advantageouslyproduced as described in Brit. Pat. No. 18292/1914 by condensing theproducts of reaction of disul'furdichloride on primary aromatic amineswith monochloroacetic acid or by any other suitable known processes.

For the oresent reaction they are best employed in form of their drysalts, preferably their difllcultly soluble heavy metal salts. Equallygood results are obtained if the acyl preferablylhe acetyl compounds ofthe o-aniiuoarylthioglydolic acids are subjected to the reaction.Finally suitable azodyestuffs, prepared by diazotizing theoaminoarylthioglycolic acids and coupling them with azodyestufl'components particularly with phenols, naphtols or theirsultonic acids,may be treated with acid con- Application filed February 7, 1924;Serial-No. 691,276.

densing agents. The dyestufi's tlius obtained still contain the 'azogroup iin their molecule, by treating them with reducing agents insubstance or by dyeing them in the vat the azo group is split andthe'vat dyestuifs are produced in substance or on improved by'theaddition of a suitable ecatalyst as for instance boric or phosphoric,acid, or salts or sulfides of heavy metals arid so forth.

Th condensation of the o-aminoarylthi'oglycolic acids and the oxidationto the vat dyestuffs mostly takes place simultane' usly, but thereaction may also be carried 0 t in two separate phases. g

The condensation of the o-aminoarylthioglycolic acids may be carried outat so low a temperature that only'the oxythionaphthenes .ornaphthoxypenthiophenes respectively, are formed whichthen can beoxidized to the dyestuffs in a sepaarte action. By this variation of theprocess the formation of by-products can be avoided.

The following examples illustrate the nature of our invention and inwhat manner it is to be performed.

E trample 1".

. condensing theproduct of reaction of disulfurdichloride on o-toluidinewith C1 b.GHaCOOH monochloroacetie acid in a dilute caustic v.

soda solution.

solution is then neutralized and an excess of coppersulfate is addedwhereby the difli" This process is in detail described in Brit. Pat. No.18292/1914. This cultly soluble copper salt, is separated, it isfiltered, washed and drie 5 kilos of the copper salt thus producedvolumes-of chlorosulfonic acid are allowed to run in slowly. -Thetemperature commencesagain to riseand the color of the mass becomessteel blue to deep pure blue. After standing for some hours the mass iswarmed to about 50 C. and kept at this tern erature until the formationof the dyestuti is finished.

The mass is then cooled down and poured on to ice. The dyestufi'produced; separates as adult blue precipitate it is filtered, washeduntil itis neutral and purified if necessary by extracting. it with awarm dilute sodium carbonate or caustic soda solution. In a dry state itforms a dark blue powder insoluble in water and the usual organicsolvents, soluble with a pure blue color in concentrated sulfuric acid,forming with an alkaline hydrosulfite solution a greenish yellow vat anddyeing animal and vegetable fibre from such a bath grey blue to darkblue shades fast to severe washing, milling and light.

Instead of the copper salt other suitable salts as for instance thecarefully dried-zinc or sodium salt of the above namedo-aminoarylthioglycolic acid may be used, and similar dlyestufis areobtained it oaminoarylthiog ycolic acids of the following structuralformula: NH

scmcoon,

scmcoon Example 2.

aqueous solution of the sodium salt of the o-aminoazylthioglycolic acidof the foregoing example is diazotized and then combmed in the usualmanner with the corresponding quantity of 6 naphtholdisulfonic acid R.The uzodyestulf thus prepared is salted out, filtered and dried.

The conversion of it to the dyestufi' of the thioindigo series iscarried out as described in Example 1. Thus produced it still containsthe azo. radical and dissolves with a claret red color in water. Bytreating it with suitable reducing agents, for instance bywarming itwith a sodiumsulfide solution, or if dyed in an alkaline hydrosulfitesolution the azo-group'issplit and a vat dyestufi' is obtained which inall its properties is identical with that of the foregoing example.

Example 3.

An aqueous solution of the sodium salt of the (2} aniinonaphthalene (1)thioglycolic acid is prepared for instance as described in Brit. Pat.Nos 18292/1914 by condensing 18 kilos of the product of reaction ofdisuljurdichloride on B naphthylaminehydrochloride with thecorresponding quantity of .monochloroacetic acid in dilute caustic sodasolution. For the formation of the acetyl compound it is almostneutralized and then 10 kilos of acetic acid anhydride are at once addedto it whilst stirring vigorously. The acetylation is finished within ashort while the solution is then acidified with mineral acidsand allowedto stand for some time whereby the (2) acetylarnino-na hthalene (1)thioglycolic acid separates in orm of a.

Ipreci 'aitate. It is filtered white crystalline ting point in a purestate and dried, its me is 185C.

40 kilos of the weli aminonaphthalene (1) produced are stirred into a utfive times their quantity, oi chlorosulfonic acid whilst cooling well;stirring. is continued until all the acid is one into solution and careis "taken that t' e temperature of the mass;- during the whole time ofthe reaction, does not rise considerably above 0? G. For finishing thereaction the mass mellowed to stand for some hours and then p ouredonice, Y filtered and washed with watcr until It 1sv neutral The productof condensation ithe penthiophene derivative of the following probablestructural formula:

-cnfl Cpl? a NECOOE f is thus obtained in form of a yellowish round (2)see 1-. th ioglggolic acid tii us crystalline precipitate,for'converting it into 4 the vat dyestufiit is mixed wim some spirit,

A/NHCOCHi /\|/NHCOCH;

separates in greenish blue flakes it is filtered,

well washed and thus obtained in afinely di-' vided paste which is welladapted for dyeing and printing purposes. It dyes cotton in an alkalinehydrosulfite solution, preferably at ordinary temperature greenish blueshades which are distinguished by their, unusual brightness and theirexcellent fastness to l1 'llt.

i-Iaving now particularly described and set forth the matter of our saidinvention and in what manner the same is to be performed, v

we declare that what we claim is:

1(As new products the vat dyes of the thioindigo series derived bycondensation with acid condensing agents from o-aminoarylthioglycolicacids of the following general formula:

wherein Ar denotes an arylgroup which may or may not otherwise containsubstituents such as alkyl, halogen, oxyalkyl, X indicates NIL, NH acyland the group N N amcomponent and Y indicates hydrogen which may besubstituted by a metal, those dyestufis possessing the following generalstructural formula:

wherein. Ar signifies an arylgroup, which may or may not otherwisecontain substituentssuch as alkyl, halogen, oxyalkyl, X indicateshydrogen which may be substituted by an acylgroup, and in which the Satom of the thioindigo ring stands in the o-position to NHX being in adry state dark colored powders, insoluble in water and the usual organicsolvents, forming with an alkaline hydrosulfite solution easily solubleyellowish colored vats from which animal and vegetable fibres are dyedvarying shades ranging from blue to black which are dis tinguis ed bytheir especially good fastness to light.

EL The herein described new vat dycstulf of the following probableconstitutional formula:

derived by condensat1on with acid condensing agents from the (1) methyl(5) chloro- (2) aminophenyl (3) thioglycolic acid, being n a dry state adark blue powder insoluble in water and in the usual organic solvents,

soluble with a pure blue color,\; in concentrated sulfuric acid, formingwith an alka;

line hydrosulfite solution a greenish yellow vat and dyeing wool andcotton from such a bath grey blue to dark blue shades fast to milling,severe washin and light.

' 3. The herein descri ed new vat dyestufi, of the following probableconstitution:

@NHCOCH;

derived from the 2) acet laminonaphthalene (1) thioglycohc acid ycondensing it with acid condensing agents to the penthiophene derivativeof the following probable constitution: v

CHI

| reas guished by their unusual brightness and their excellent fastnessto light.

In witness whereof we have hereunto signed our names this 18th day ofJanuary 1924.

RICHARD HERZ. JENS MULLER. Witnesses:

HERBERT STEIGER, GABRIELE FLEsoH Certificate of (brrectioxi.

It is hereby certified that in Letters Patent No. 1,498,913, grantedJune- 24, 1994,

upon the application of Richard Herz, of Frankfort-on-the-Main, andJens'Miiller,

of Hanan, Germany, for an improvement in Vat Dyes of the ThioindigoSeries and Processes of hlal'zin Same, errors a car in the rinted'ecification re mil"- 0 PP P P 1 ing correction as follows: Page 1, line23. after the word metal Strikeout the period and insert a comma and theW0 Ids if treated with acid condensing agents. are converted in/Z0 newand wry mefu/ rig/cstu-fl's-of the thim'ndz'go eerie dyeing animal anduegezable fibres in file alkaline hydrosulfite 'vat varying EWZS rangingfrom blue to black, which m diszlZ- mlshed by their especially-goodfastnesa to light; same page, line 65, for the misspelled word sepaarteread's'epdr ate';

and that the said Letters Patent should be read with these correctionstherein that the same may conform to the record of the. case in thePatent Ofioe.

Signed and sealed this 2d day of September, A. D. 1924:.

SEAL KARL FENNING,

Acting Commissioner of Patents.

